[Zope3-Users] Re: Referencing objects in auto-generated forms

[Gary Poster]

On Apr 18, 2006, at 3:31 AM, Frank Burkhardt wrote:

> Hi,.
>
> On Sun, Apr 16, 2006 at 01:48:37PM -0500, Jeff Rush wrote:
>
> [snip]
>
>> Frank, I thought vocabularies were being de-emphasized though, in  
>> favor of the newer 'sources' component?
>> Vocabularies were good for short lists of choices, but because it  
>> read them all into memory at once not so good
>> at lazy evaluation.  Sources supposedly uses an iterator and is  
>> good for both short and long lists, as I roughly
>> understand it.

No, actually, both can be used for infinite choices or finite  
choices.  The primary difference to me is purity: sources break apart  
the token functionality--an aspect of display that widgets need--from  
the data definition.

Up until fairly recently (i.e., post-3.2, I believe) you couldn't  
even express a finite source.

There are still more vocabulary widgets than source widgets in  
zope.app.form.

Sources are slated to replace vocabularies, but the uptake has been  
slow: I don't know of a hard date.

Gary